[development] removal of unused and low stakes code related to Cry-threading (#2896)

Removal highlights include:
 - File indexer (used CryThread<>) linked to long gone asset browser
 - Producer/consumer queues from CryMT
 - set/vector/CLocklessPointerQueue containers also from CryMT
 - Cry interlocked linked list and _InterlockedCompareExchange128
 - CryThread type
 - SAtomicVar types
 - CryAutoSet type
 - Various unused lock types
 -- AutoLockModify
 -- AutoLockRead
 -- CryOptionalAutoLock
 -- CryReadModifyLock
 -- CryRWLock
 -- ReadLock
 -- ReadLockCond
 -- WriteAfterReadLock
 - Misc. unused functions
 -- CryInterLockedAdd (not to be confused with CryInterlockedAdd, using a lower case "locked")
 -- CryInterlockedExchange64 (which was only defined for unix platforms)
 -- SpinLock
 -- JobSpinLock
 -- AtomicAdd
 -- JobAtomicAdd

Signed-off-by: AMZN-ScottR <24445312+AMZN-ScottR@users.noreply.github.com>

Code/Editor/CryEdit.cpp

@@ -127,7 +127,6 @@ AZ_POP_DISABLE_WARNING
 
 #include "Util/AutoDirectoryRestoreFileDialog.h"
 #include "Util/EditorAutoLevelLoadTest.h"
-#include "Util/IndexedFiles.h"
 #include "AboutDialog.h"
 #include <AzToolsFramework/PythonTerminal/ScriptHelpDialog.h>
 
@@ -1715,18 +1714,6 @@ BOOL CCryEditApp::InitInstance()
 
     if (IsInRegularEditorMode())
     {
-        CIndexedFiles::Create();
-
-        if (gEnv->pConsole->GetCVar("ed_indexfiles")->GetIVal())
-        {
-            Log("Started game resource files indexing...");
-            CIndexedFiles::StartFileIndexing();
-        }
-        else
-        {
-            Log("Game resource files indexing is disabled.");
-        }
-
         // QuickAccessBar creation should be before m_pMainWnd->SetFocus(),
         // since it receives the focus at creation time. It brakes MainFrame key accelerators.
         m_pQuickAccessBar = new CQuickAccessBar;
@@ -2163,12 +2150,6 @@ int CCryEditApp::ExitInstance(int exitCode)
         }
     }
 
-    if (IsInRegularEditorMode())
-    {
-        CIndexedFiles::AbortFileIndexing();
-        CIndexedFiles::Destroy();
-    }
-
     if (GetIEditor() && !GetIEditor()->IsInMatEditMode())
     {
         //Nobody seems to know in what case that kind of exit can happen so instrumented to see if it happens at all